Been thinking a lot about white tea, with its elusive flavor. Specifically, have been fascinated by the compositional differences between white tea and green tea: in fact there are few differences, yet white tea’s aroma is so much more elusive than that of green tea. Why?
To my delight, found a paper that includes white tea in its analyses (most only consider green, oolong, and black).* I thought I may have found the answer…
According to the data in this paper, the difference doesn’t seem to lie in the usual “green” compounds, such as hexanal, with its flavor of cut grass (yes, cut grass emits this chemical), nor in the citrusy flowery compounds such as E-geraniol and linalool, which help give both green and white tea their rose-like and citrus-like aromas. Rather, it seems that the critical difference lies in the presence of nerolidol in green teas and its relative absence in white teas.
Nerolidol has a green, citrus flavor, but most importantly it provides much of the woody flavor that we expect in tea. In perfumery, it is considered a base note that serves as a fixative for other aromas, while providing a subtle addition for blending flower and citrus top notes.** In other words, it is an aroma that has staying power, and may, if the data in this paper are correct, give green teas the flavor “heft” that is missing from white teas. One can almost think of it as a dial that increases the “volume” of the other green ingredients in the tea.
So I looked further into nerolidol, and found a paper on the nerolidol content of teas, including white tea.*** In this analysis, white tea and green tea have virtually the same amount of nerolidol…so what to think now?
(Citrus aurantium subsp. amara or Bigaradia —you can see the green fruit in the upper right corner).
Nerolidol is one of the characteristic compounds in neroli flower oils. Image from moreguefile.com.
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* Kunbo Wang, Fang Liu, Zhonghua Liu, Jianan Huang, Zhongxi Xu, Yinhua Li, Jinhua Chen, Yushun Gong, Xinghe Yang. Comparison of catechins and volatile compounds among different types of tea using high performance liquid chromatograph and gas chromatograph mass spectrometer: Catechins and volatile compounds. International Journal of Food Science & Technology, ISSN 0950-5423, 07/2011, Volume 46, Issue 7, pp. 1406 - 1412.
**https://www.perfumersworld.com/product/nerolidol-3LM00319; http://www.aftelier.com/Nerolidol-p/bot-nsio-nerolidol.htm
*** Chunhua Ma, Yanqin Qu, Yingxue Zhang, Bin Qiu, Yiru Wang, Xi Chen. Determination of nerolidol in teas using headspace solid phase microextraction–gas chromatography. Food Chemistry. Volume 152, 1 June 2014, Pages 285–290.
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